Dossier - The Professor part 7

Head back out to the previous room and opt to take the ignored door on the right. This will ultimately lead to another small room with a staircase leading downward and to the right. There are a few enemies to deal with here, all located on the far side of the room. Take them out before opening the door to reach the staircase, as you have plenty of cover to work with. Once the enemies have been slain and the door has been open, dash down the stairs and toggle over to your sniper rifle. As soon as you turn leftward through an open door, you'll see an enemy off in the distance on a balcony. This foe is shooting rockets from the safety of that location, and the only realistic way to deal with him is to use your sniper rifle to its fullest capacity. Once that lone enemy is dead, you can continue forward along the catwalk towards his location.

As you walk along the catwalk and begin to turn rightward, keep that sniper rifle ready, because more rocket-chucking foes sit on balconies across the chasm. In addition to the enemies on the balconies, there will be a slew of Blood Pack Troopers gathered in the area below. The best technique to utilize here is to first use your sniper rifle to be sure that all rocket-launching enemies on the balconies across the way are downed. Then, switch over to your machinegun (or other weapon of choice), and begin to lay into the enemies in the area below, from the safety of your own balcony. Use the explosives strewn all around the area to your advantage, and if an enemy or two eludes you from above, go down one of the three staircases leading off of your balcony, and engage them in closer combat (all three staircases lead to the same area). Surprisingly, while there's ammunition lying around for you post-battle, there are no items for you to gather otherwise.

When you're ready, press through the two doors that the Vorcha earlier poured out of. On the other side of the second door, you'll meet up with a few more Blood Pack enemies, but nothing you can't handle (take cover behind the door you came through when the enemies reveal themselves, as you'll be fighting in close quarters here, and can be easily felled if you aren't careful). With those thugs down, explore the right side of the room for a medical kit on the wall, and then head leftward and forward towards a series of up-leading staircases. Your party members will comment that you're almost to the environmental plant. Good thing, as you're likely getting fairly fatigued by this point.

When you reach the door at the top of the stairs, press on through it. You'll find yourself in the environmental control room. This is the place you wanted to get to in order to disperse the cure to the disease through the air ducts in the Quarantine Zone. However, when you arrive, you'll find that the Vorcha got there first. Electrical and air disruptions felt back at the clinic are the work of these guys, who are trying to break all of the machines around them. However, these guys aren't too smart, either. They quickly let loose that they are, in fact, working for the Collectors, so be sure to press them on what the Collectors want before hostilities inevitably ensue.